I was exploring a low-cost method to get mobile broadband in the car. The Huawei E122 was the cheapest 3G dongle on ebay – only USD19.99. I bought it, along with the TP-Link TL-WR703N, a compact, USB-powered router that supports 3G dongles. The E122 isn’t listed as a supported 3G modem, and it indeed isn’t supported.
My next step was to flash OpenWRT on it. To my surprise, it didn’t work either. I Googled and tried several things, but nothing worked until I tried the commands I found in an over three-year-old thread on Ubuntu Forums. The very last post by the thread starter himself, mvip, posts a wvdial config file that he says he managed to get working for his E122. I simply translated it into a chatscript (used by OpenWRT). And…
Now I have Wi-Fi in my car, cobbled together for under USD50.
My chatscript for the E122:
ABORT BUSY ABORT 'NO CARRIER' ABORT ERROR REPORT CONNECT TIMEOUT 10 "" "ATE0" OK "ATZ E0 V1" OK "AT+CFUN=1" OK 'AT+CSCS="UCS2"' OK "AT+CREG=2" OK "AT+CGREG=2" OK "AT+COPS=3,2;+COPS?" OK 'AT+CGDCONT=1,"IP","$USE_APN"' SAY "Calling UMTS/GPRS" TIMEOUT 30 OK "ATDT*99***1#" CONNECT ' '